package y_2025.m03.d08.t02;

public class WhileSum {
    public static void main(String[] args) {
        int sum = 0, i = 21; // 直接遍历21的倍数
        while (i <= 1000) {
            sum += i;
            i += 21;
        }
        System.out.println("和为：" + sum);
    }
}